Paul Dibb and Richard Brabin-Smith recently opined that our strategic situation has changed for the worse and that the warning time clock is ticking. I think they’re right. We were able to cruise through the post–Vietnam War period without doing too much thinking about our strategy or force structure (though don’t tell Paul or Brab I said that) because there was nothing major to worry about in our hemisphere. That’s clearly far from the case now. The question is, then, ‘What do we do about it’?

Dibb and Brabin-Smith’s prescription is for an overhaul of our force preparedness, with a possible future step of developing an anti-access and area denial (A2AD) strategy. Hugh White’s response mostly agrees, but cautions that a lot of thought, work and money—he has previously suggested in excess of 2.5% of GDP—would be required to develop the forces that could withstand a Chinese assault on Australia. He also makes the important observation that the ADF force structure would look very different from the one we’re in the process of spending a couple of hundred billion dollars on. White is a long-term advocate of a ‘focused force’ that is more heavily weighted towards A2AD.

But before we can start redesigning our military forces, or doubling down on defence spending, we need to come up with answers to some fundamental questions. Why would China attack Australia? If it did, what form might an attack take? And—the biggy—how do we propose to counter China’s nuclear arsenal?

A possible answer to the first question is that prudent planning worries more about capability than about intent. If a regional country has the capability to attack us, so the reasoning goes, then we’d better be able to defend ourselves should they choose to do so. ‘Capability over intent’ has been something of a mantra in Australian defence planning for decades now, and it was a handy excuse to keep buying replacements for ageing force structure elements in the absence of any obvious hostility in our extended neighbourhood.

But that’s a poor reason to divert hundreds of billions from hospitals, schools and the NDIS. Optimists can make a plausible case that China already has ready access to Australian natural resources and is well down the track to securing its own part of the world from external threats. They might also add that nothing in President Xi Jinping’s China vision seems to suggest expansionism beyond those territories that China has claimed at various times throughout its long history.

But I think there are plausible ways in which Australia and China could fall out badly enough to make the use of armed force possible. The most likely is by Australia taking the American side in a conflict between China and the United States. But even if the US largely opts out of Asian affairs in the future, we could still get into China’s sights. It would be morally questionable for Australia to continue to do business as usual with Beijing if, for example, China attacked Japan or Taiwan—both of which are credible possibilities—or another neighbour, such as Vietnam. An Australian embargo of exports to China could put us on a collision course (as it did with Japan in 1941).

So Dibb and Brabin-Smith might be right about the possibility of a future conflict with China. Or at least it’s plausible enough to require defence planning. The next question is what sort of conflict might we find ourselves in? Here’s where a little more caution is required. Australian strategists are much too glib when talking about ‘our region’. Geography still matters, especially where power projection is concerned. Listening to local debates, you could sometimes be forgiven for thinking that Australia and China share a Colorbond fence down the sideway. To seriously threaten Australia with conventional force, China would need to develop considerably more long-range power-projection platforms than it currently has, or even has planned. This isn’t Europe. We don’t share a land border with our potential adversary—there’s an intercontinental distance between us and China.

Realistically, rather than invasion or large-scale disruption, we’re talking about strikes against Australian targets of the sort that the US can launch today from its surface vessels, long-range aircraft and submarines. To hedge against that, we’d need to do exactly what China has been busy doing for the past 20 years to counter possible American strikes: develop an A2AD capability. In that respect, Dibb, Brabin-Smith and White are spot-on—the defence force needed to do that is quite different from the one we’re about to invest in. For a start, we wouldn’t be building a dozen large warships. We would be building more submarines, aircraft and missiles that could threaten Chinese power-projection assets. (Incidentally, I think we could do that with a defence budget not much bigger than today’s if we were prepared to make the tough calls on priorities.)

But there’s still one thing missing. China is a nuclear power. If it really wanted to threaten Australia, it wouldn’t be limited to threatening strikes with relatively small conventional weapons. That’s the element that sets the Australia–China scenario apart from today’s China–US dynamic in which both sides have nuclear weapons. If we seriously want to be able to independently hold China at bay, we need to counter a nuclear threat as well as a conventional one. Following their respective logics through to their conclusion, Dibb and White have both discussed the nuclear issue in recent pieces, but they both equivocate on actually suggesting that we need to go down that path. Dibb says:

There is no present requirement foreseen for Australia to develop a nuclear weapons capacity. But the history of advice to successive governments suggests, should our strategic circumstances look like deteriorating disastrously, it might be prudent to revisit reducing the technological lead time.

In his new Quarterly Essay, White says:

The chilling logic of strategy therefore suggests that only a nuclear force of our own, able credibly to threaten an adversary with major damage, would ensure that we could deter such a threat ourselves.

But he then steps back, neither ‘predicting nor advocating that Australia should acquire nuclear weapons’, while allowing that ‘it is untenable to think that this won’t mean the question will have to be re-examined’.

The coyness, and willingness to defer grappling with the logical conclusion of their arguments, effectively leaving it to future strategists, is surprising. Either our defence prospects have changed so much that we need to worry about being attacked by a nuclear-armed major power and drastically change our defence policies, or they haven’t. It’s true that extra conventional arms will provide additional deterrence in some scenarios, but almost by definition they wouldn’t involve an existential threat to our sovereignty.

There is a serious strategy discussion to be had and the recent discussion is a start, but it’s dangerously incomplete. Pursuing the force structure changes suggested by White could result in us spending many billions of dollars for little extra security. The key question, which we shouldn’t dance around, is whether we judge the risk of an attack from China to be high enough and serious enough to warrant developing an independent nuclear deterrent. Conversely, if we judge the risk to be small, doing nothing is a perfectly credible response. Sitting in between—worrying about the prospect but taking inadequate (though prodigiously expensive) steps to hedge against it—doesn’t seem very sensible.